Battle Continues Over Vietnam PTSD Numbers

Mar. 23 -- THURSDAY, Aug. 23 (HealthDay News) -- Decades after the last U.S. troops departed Vietnam, the debate still rages on how many veterans of that conflict suffered or still suffer from post-traumatic stress disorder.

Post-traumatic stress disorder (PTSD) is an anxiety disorder involving nightmares, flashbacks and panic attacks linked to event "triggers" that develop after exposure to combat or other extremely disturbing events.

In the years following the end of U.S. involvement in Vietnam, the actual number of veterans psychologically scarred by what they had encountered in the war became the subject of heated controversy.

A 1988 study, conducted by the U.S. Centers for Disease Control and Prevention, estimated a relatively low lifetime rate of PTSD among veterans of 14.7 percent.

But a second government study -- the National Vietnam Veterans Readjustment Study (NVVRS) -- calculated a much higher lifetime figure of 30.9 percent and a current figure of 15.2 percent. Both studies relied heavily on veterans' self-reports of PTSD symptoms and exposure to wartime trauma, and both drew heavy criticism.

Last August, a paper published in the prestigious journal Science downgraded the estimated percentage of Vietnam veterans suffering from PTSD to an 18.7 percent lifetime prevalence rate and 9.2 percent current rate. The variance, the authors stated, was due to differences in how they defined PTSD.

But perhaps more important, according to the authors, the Science paper confirmed a strong "dose/response relationship" between the severity of exposure to war-related stressors and PTSD. And they did not find any evidence for exaggeration in veterans' reports, a claim which had been made by some critics of the original estimates.

That paper, which relied on what the authors called a "treasure trove" of historical material not available when the NVVRS was conducted, had sought to squelch the previous controversy.

But it didn't. In fact, a new article -- one of four published in the August issue of the Journal of Traumatic Stress -- has pushed the number of estimated Vietnam veterans currently experiencing PTSD downward even further, to just 5.4 percent.